REPORT 



GEOLOGICAL SURVEY 



WISCONSIN, IOWA, AND MINNESOTA; 



AND INCIDENTALLY OI 



A PORTION OF NEBRASKA TERRITORY. 



MADE UNDER INSTRUCTIONS FROM THE UNITED STATES TREASURY DEPARTMENT. 



DAVID DALE OWEN, 



UNITED STATES (i Dlll.i )G1S T. 



PHILADELPHIA: 



LIPPINCOTT, GRAM BO & CO. 



18 52. 



